The present invention relates to a process for producing interferon which comprises culturing an interferon-producing mammalian cell in a cell culture medium containing at least one compound selected from the group consisting of ascorbic acid, an ascorbic acid derivative and a vanadium compound.
Interferon was discovered by Nagano et al (Comnt. Rend. Soc. Biol., Vol. 148, page 1700, 1954) and Isaccs et al (Proc. Roy. Soc. Ser. B., Vol. 174, Page 258, 1957) and is reported to possess an anti-tumor effect in addition to an anti-viral effect (Gressor, I. et al., B.B.A., Vol. 516, page 231, 1978). Accordingly, attention has been focused upon the possibility of utilizing interferon as a medical drug.
Presently, interferon is roughly classified into three groups, which are termed interferon-.alpha. (.alpha.-IFN), interferon-.beta. (.beta.-IFN) and interferon-.gamma. (.gamma.-IFN), respectively (Nature, Vol. 286, page 110, 1980). .alpha.-IFN is produced mainly by stimulating leukocytes with a virus, .beta.-IFN is produced mainly by stimulating fibroblasts with double-stranded RNA or a virus, and .gamma.-IFN is produced mainly by stimulating lymphocytes with a mitogen.
It is essential to devise a process for producing interferon on a large scale for evaluating interferon as a medical drug. Heretofore, production processes such as a super-induction process (Antimicrob. Ag. Chemother., Vol. 2, page 476, 1972) in which .beta.-IFN is produced in a large amount, etc. have been reported. Further, the so-called priming effect in which interferon is produced in a large amount by treating producing cells with a small quantity of interferon prior to interferon production has been provided for practical use in large scale production of .alpha.-IFN and .beta.-IFN.
However, satisfactory large scale production of interferon has not been realized with these processes. Therefore, development of a process for excellent, large scale production of interferon is desired.